Iraqi insurgency (2003-2011)

The Iraqi insurgency lasted from 1 May 2003 to 18 December 2011 in the aftermath of the invasion of Iraq, when Sunni and Shia militant groups began an insurgency against the US-led occupation of Iraq and the new Iraqi government. The insurgency escalated into a sectarian civil war in 2006, but it died down after the "troop surge" of 2007 and was almost defeated by the time that the MNF-I forces withdrew from Iraq in December 2011. The withdrawal led to the start of the Iraq Crisis, which would ultimately lead to the Iraqi Civil War.

Background
On 1 May 2003, President of the United States George W. Bush proclaimed an end to major combat operations in Iraq and famously declared "mission accomplished". The Ba'athist government of Saddam Hussein had been overthrown, but a new Iraqi government had yet to be formed, and many pockets of resistance still remained after the start of the US occupation. The country had no history of democratic politics and was split between a Muslim Shia majority previously persecuted by Saddam, a Sunni minority he had used to control the country, and Kurdish separatists in the north. The country’s infrastructure lay in ruins. With little or no power or water, cities were barely functioning. The one institution that had united the country - the pro-Saddam army - was immediately dismantled. The Coalition therefore had to set up a provisional authority to govern the country until democratic elections could be held and a new government formed.

War
The shift from liberator to unwantled occupier was swift, as Iraqis turned against Coalition forces. Much of the dissent came initially from the "Sunni Triangle” in the center of the country. The insurgents were mainly Saddam loyalists and Iraqi nationalists upset at their loss of power, but dissent soon spread to Sunni clerics and their followers. In 2004, the insurgency spread to Shia clerics and radicals who, inspired by neighboring Iran, saw US troops in particular as an anti-Islamic force. As the security situation deteriorated, foreign ﬁghters and the newly created al-Qaeda in Iraq contributed to the violence as a way of attacking the USA. The main areas of conﬂict were in the poor Shia sections of Baghdad and other cities and around Fallujah in the center of the Sunni Triangle. Two bitter battles for Fallujah took place in 2004, the second, in November, lasting 46 days. The US military described the battle as the heaviest urban combat it had been involved in since the Vietnam War. While US troops and installations were the main targets, Sunni suicide and car bombers also targeted Shia mosques and other civilian meeting places in an attempt to stir up sectarian hatred. By 2006, 33 people a day on average were being killed in Baghdad alone. The violence resulted in the ethnic cleansing of many cities, the Shia majority driving Sunnis out of their homes and establishing control at their expense. In order to suppress the rising violence, 20,000 additional US troops were sent to Iraq in early 2007 to contain the situation. This "troop surge appeared to work, reducing violence across the country, although Sh’ia dominance over their rival Sunnis probably contributed more. The reduction in violence allowed the US to start withdrawing troops, slowly handing over security duties to the reconstituted and re»equipped Iraqi Army and the government of Iraq's 18 provinces to locally elected politicians. In 2008, the US and Iraqi governments approved a Status of Forces agreement, agreeing that US forces would leave Iraqi cities by 30 June 2009, and that all US forces would leave the country by the end of 2011. On 1 January 2009, the US handed over the Green Zone security region in the center of Baghdad to Iraqi security forces. Britain announced that its troops would all withdraw by the end of July 2009. Other Allied troops had been withdrawn by the end of 2008. By 2010, car bombings declined to an average of 10 a month, and multiple-location bomb attacks occurred only twice or thrice a year. On 28 December 2011, the last US troops withdrew from Iraq and into Kuwait, ending the first phase of the Iraqi insurgency.

Aftermath
The death toll during the invasion and occupation of Iraq is hard to estimate, as many deaths went unreported. The Iraqi death toll between March 2003 and 2009 may have been around 1.2 million people, almost five percent of the population. Half were killed in shootings, a fifth by car bombs. One in five Iraqi families lost at least one member. The occupation also led to a deterioration in relations and increasing animosity between the US and Islamic states, notably Iran, and undermined the US's status as the "global policeman." In Afghanistan, the Taliban regained strength as the US concentrated its military efforts in Iraq.